SPORT BOOT LINER AND METHOD FOR MAKING SAME

Description

FIELD OF THE INVENTION

[0001] This invention relates to a method for making a custom fitted liner for a sport boot, to a liner for a sport boot such as a ski boot, and to a sport boot incorporating such a liner.

BACKGROUND OF THE INVENTION

[0002] Specialized boots are used in many sports such as skiing, snow boarding, ice skating, roller skating, and in-line roller skating. A widely used construction for a sport boot has a rigid or semi-rigid outer shell and a padded inner liner. It is important that the liner fit the wearer well if maximum performance is to be achieved.

[0003] In such boots, the outer shell of the boot and the inner liner open to permit entry of the wearer's foot. After the wearer's foot is in place, the outer shell is fastened shut with buckles, laces, or some other fastening means to hold the liner snugly around against wearer's foot and lower leg.

[0004] Three characteristics that are required in most high performance sport boots are lateral stiffness, a degree of forward flex at the ankle and a snug fit to provide the wearer with fine control over the motion of the boot. For example, in a ski boot, lateral stiffness is required to allow the skier to control the angle of the edges of the skis relative to the snow; forward flex is required to allow the skier to move his or her centre of gravity relative to the ski and to allow the skier to bend at his or her ankles to accommodate changes in the terrain; and, a snug fit is required so that small motions of the skiers foot are translated into precise changes in the position of the ski attached to the boot.

[0005] A problem faced by sport boot manufacturers is to design a boot capable of maintaining a snug fit around the wearer's calf and heel when the wearer flexes his or her leg forward in the boot. Flexing forward tends to cause the wearer's heel to lift. This problem is made worse because the pressure of the wearer's shin on the front of the boot liner tends to enlarge the opening in the upper portion of the liner. This makes it easier for the wearer's calf to pull away from the back of the boot liner when the wearer flexes his or her leg forward at the ankle.

[0006] Prior art sport boot liners have the disadvantage that the pressure of a wearer's shin on the front portion of the liner tends to cause the portion of the liner which encircles the wearer's leg at the cuff to loosen. This generally occurs because the closure in conventional boot liners opens when pressure is placed on the shin portion of the liner. For example, in a boot liner with a conventional front closure comprising a slit covered by a conventional tongue, the pressure of the wearer's shin on the tongue will cause the tongue to slip forward relative to the rest of the liner when the wearer's leg is flexed forward, thereby causing the liner to loosen around the wearer's calf.

[0007] Boot manufacturers have devised various attempted solutions to this problem. Most of the attempted solutions include providing fastening means associated with the boot shell for closing the shell tightly around the inner liner at the cuff. A disadvantage of keeping the liner snugly fitted about the wearer's calf and shin even when the wearer's leg is not flexed is that it can cut off blood circulation in the wearer's foot and lead to discomfort. Some manufacturers provide boots having various designs of clamp to positively hold the wearer's heel down. These designs can cause pressure points on the wearer's heel and achilles tendon area. They also require precise adjustment to accommodate the foot of an individual wearer.

[0008] Another problem faced by sport boot manufacturers is to provide a comfortable sport boot liner which provides good control by closely fitting the top of a wearer's foot, especially in the region of the forefoot just in front of the wearer's ankle.

[0009] US-A-3,786,580, Dalebout discloses a double-walled inner liner for a sport boot which can be custom moulded to a wearer's foot by injecting a foamed elastomeric material under pressure into a cavity between the walls in the liner. This boot liner has disadvantages which are well known in the art in respect of injectable foam liners. The Dalebout liner has a forward facing slit opening for entry of a wearer's foot. The opening is closed by a narrow leather flap and is surrounded by padded material. The design of the opening does not permit the liner to be moulded to a wearer's foot in the vicinity of the opening.

[0010] FR 2,435,217, Blanc discloses a method for forming a sheet of thermoformable plastic material to the shape of the bottom of a wearer's foot. The method involves the steps of heating a sheet of the thermoplastic material, placing it inside an inflatable slipper, fitting the slipper around a wearer's foot and inflating the slipper to press the material against the bottom of a wearer's foot. This method does not provide any fitting in the areas of the wearer's Achilles tendon, ankle or shin.

[0011] EP-A-0 004 829 discloses various items of sports equipment which comprise rigid outer shells with pads comprising a heating element sandwiched between layers of thermoformable plastic material bonded to the outer shells at selected points. These items of sports equipment require embedded heating elements and do not disclose a design which can be fitted closely to a wearer's forefoot area or which provides for a front opening.

[0012] FR-2 460 118 discloses a sock like ski-boot liner made of a thermally expandable material. The liner is fitted to fill the voids between a boot shell and wearer's foot by heating the liner with an electric heating element.

SUMMARY OF THE INVENTION

[0013] The invention provides a method for forming a custom-fitted sport boot liner for wearing inside a sport boot shell. The method comprises the steps of: providing an unfitted liner comprising a thermoformable material, said material having a thermoforming temperature, said unfitted liner having a hollow foot receiving portion and a hollow lower-leg receiving portion, said lower-leg receiving portion comprising first and second side edges, said side edges defining free edges of first and second wings; heating said unfitted liner to a temperature above said thermoforming temperature; placing a person's foot and lower leg into said unfitted liner with said foot in said foot-receiving portion and said lower leg in said lower-leg receiving portion; wrapping said first wing in front of said person's lower leg in a first direction; wrapping said second wing in front of said person's lower leg outside of and overlapping with said first wing in a second direction opposite to said first direction; placing said person's foot and lower leg and unfitted liner inside said sport boot shell to simultaneously shape an inside surface of said unfitted liner to conform to said wearer's foot and an outside surface of said unfitted liner to conform to an inside surface of said sport boot shell; and allowing said unfitted liner to cool to a temperature below said thermoforming temperature.

[0014] The invention also provides a sport boot liner for wearing inside a sport boot shell. The liner comprises: a hollow generally horizontal foot receiving portion having a central longitudinal axis; and a hollow generally vertical lower-leg receiving portion comprising a calf receiving portion a shin receiving portion, an ankle-receiving area adjacent the ankle of a human wearer of said liner; a cuff circumscribing a rounded opening, said cuff being above a horizontal plane through said ankle-receiving area; and first and second side edges said side edges defining free edges of first and second flaps overlapping in a forward facing overlap area; wherein said first flap is wrapped in a first direction across said overlap area and said second flap is wrapped across said overlap area in a second direction, opposite to said first direction, and outside of said first flap and said overlap area extends at least over a region between said horizontal plane and a point adjacent said wearer's forefoot and spaced forward from said ankle-receiving area.

BRIEF DESCRIPTION OF THE DRAWINGS

[0015] By way of illustration the invention will now be described with reference to the following drawings which illustrate specific embodiments of the invention but which should not be construed as restricting the scope or spirit of the invention in any way:

Figure 1 is a top view of an alpine ski-boot liner according to the invention;

Figure 2 is a perspective view of the ski-boot liner of Figure 1;

Figure 3 is a section along line 3-3 of the ski-boot liner of Figure 1;

Figure 4 is a section along line 4-4 of the ski-boot liner of Figure 1;

Figure 5 is a plan view of a blank of sheet material cut to form the liner of Figure 1;

Figure 6 is a perspective view of an unfitted liner capable of being formed into the ski-boot liner of Figure 1;

Figures 7A through 7J illustrate the steps in a method for making the liner of Figure 1;

Figure 8 is a schematic top plan view of the cuff of a ski boot comprising the boot liner of Figure 1;

Figure 9 is a perspective view of an alternative liner according to the invention; and

Figure 10 is a plan view of a blank of sheet material cut to form the liner of Figure 9.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT

[0016] For clarity the invention will now be described as embodied in a method for making a liner for an alpine ski-boot and the resulting liner. Many other varieties of sport boot such as skating boots and snow boarding boots may also be constructed according to the invention in ways which will be obvious to one who understands the following description. Also, a liner according to the invention may be constructed according to other methods.

[0017] Figure 1 shows a sport-boot liner 20 according to the invention. Liner 20 is in the form of a contoured sock which surrounds a wearer's right foot, calf and shin inside an outer boot shell 25 (Figure 7I). Liner 20 has a shin area 27 which contacts a wearer's shin and a portion of the top of the wearer's foot, a calf region 29 which contacts the wearer's calf and a heel region 31 which contacts the wearer's heel. A liner for wearing on the wearer's left foot would be a mirror image of liner 20.

[0018] Shin area 27 comprises a pair of overlapping flaps 34, 36. Inner flap 34 and outer flap 36 each wrap completely around the front of the wearer's shin. Preferably outer flap 36 wraps toward the outside of the wearer's foot and inner flap 34 wraps toward the inside of the wearer's foot. In a liner to be worn on a right foot, outer flap 36 preferably wraps in a clockwise direction and inner flap 34 wraps in a counter-clockwise direction. The opposite applies to a liner for a left foot.

[0019] Free edge 54 of inner flap 34 and free edge 56 of outer flap 36 may be tapered in thickness so that there are not any sudden large changes in thickness of liner 20 which would be likely cause pressure points on the wearer's leg or foot. Outer flap 36 is preferably indented along free edge 54 of inner flap 34 so that free edge 54 does not press uncomfortably into the leg of a wearer.

[0020] Flaps 34 and 36 form a double thickness of material in shin area 27 when liner 20 is being worn. The uppermost portions of flaps 34 and 36 extend generally vertically along the shin of a wearer. In their portions below a horizontal plane through the wearer's ankle, flaps 34 and 36 curve upwardly and extend along the top of the wearer's foot to Point 39. Point 39 is preferably situated centrally on the wearer's forefoot (metatarsus) behind the wearer's toes and between the forward portion of the wearer's arch and the region generally above the ball of the wearer's foot. Point 39 may be located within 1.5 cm of a wearer's meta-tarsal joint. Flaps 34 and 36 overlap in an area extending from point 39 to cuff 38. The region 80 of the area in which flaps 34 and 36 overlap below approximately a horizontal plane passing through the ankle of a wearer curves to follow generally the contour of the wearer's forefoot. In region 80 flaps 34 and 36 have a compound curvature following the saddle-like shape of the wearer's shin, ankle and forefoot. Liner 20 can be easily opened for inserting or removing the wearer's foot by grasping flaps 34 and 36 and peeling them outwardly. The dashed lines in Figure 2 show flap 36 in a peeled back position.

[0021] Liner 20 can be made from a blank 40 of sheet material 42 cut as shown in Figures 5 and 7A. The correspondence between the parts of liner 20 shown in Figures 1 and 2 and the parts of blank 40 shown in Figure 5 is as follows: edge 50 corresponds to the top edge of cuff 38; edge 51 corresponds to the free edge 54 of inner flap 34; edge 49 corresponds to the free edge 56 of outer flap 36; points 47 and 48 correspond to point 39; edges 52 and 53 correspond to seam 55; and point 46 corresponds to the heelward end of seam 55.

[0022] Material 42 is preferably a material which is thermo-formable at a temperature low enough that it can be thermoformed while in contact with a wearer's foot while maintaining a surface temperature low enough not to burn the wearer's foot. For example, ULTRALON™ 7.0 pound closed cell EVA foam made by Ultralon Products (N.Z.) Ltd. of Christchurch New Zealand is a suitable material. This material provides good cushioning for the wearer's foot and yet is firm enough to provide good control of the boot. It is also warm, durable, and is easy to form into a boot liner as described below.

[0023] It is highly preferable that material 42 is custom formable. To achieve excellent control of the boot it is desirable that liner 20 be fitted to the wearer's foot in region 80. The human foot has several tendons that pass through the area near point 39. If liner 20 were not custom fitted to the wearer's foot in the area near point 39 then liner 42 would be extremely uncomfortable unless it were made of a soft material in region 80 in which case it would not provide optimum control.

[0024] Before being cut to form blank 40 material 42 is preferably laminated on both sides with a layer of fabric 44. Fabric 44 may be, for example, a four-way stretch fabric comprising 79% Nylon and 21% Lycra. Preferably fabric 44 is a slightly heavier weight on the side of material 42 that will become the outside of liner 20. Fabric 44 may be applied by spraying material 42 and fabric 44 with a uniform coating of a suitable adhesive, such as 3-M™ model 77 spray adhesive, and laminating fabric 44 to material 42 under pressure. After fabric 44 has been applied to both sides of material 42 then blank 40 may be cut out by any suitable means such as die cutting.

[0025] Fabric 44 somewhat stiffens liner 20. Fabric 44 makes liner 20 easier to put on than an unlined liner 20 and improves the comfort of liner 20 by making liner 20 less clammy than an unlined liner 20. Fabric 44 also helps to prevent heat loss from material 42 during fitting so that material 42 is retained above its thermoforming temperature for a longer time. This makes the fitting process described below more reliable because it allows more time to complete the fitting. Furthermore, the slight stiffness of fabric 44 helps to prevent wrinkles from forming during fitting.

[0026] Blank 40 is preferably prepared by routing a groove (not shown) between points 47 and 48 along edges 49, 50 and 51. The edges of the routed groove are then stitched together to form a finished tapered edge as shown in Figure 3. Blank 40 is formed into an unfitted liner 60 (Figures 6 and 7C) by bringing points 47 and 48 together and joining side 52 to side 53 between point 46 and points 47 and 48 to form a seam 55. Seam 55 can be made by stitching or, if material 42 is weldable, by welding. However, seam 55 is preferably made by bonding with a suitable adhesive and stitching along the resulting joint (Figure 7B). The adhesive used to form seam 55 preferably does not harden when it is chilled. If the adhesive in seam 55 does harden at low temperatures then the hard adhesive could cause pressure points on the wearer's foot when liner 20 is worn skiing or in other cold weather sports. It has been found that when material 42 is the ULTRALON™ closed cell foam described above that HELMIPRENE™ model C8130-3 glue made by the Helmitin company is a suitable adhesive. As shown in Figure 4, seam 55 is preferably stitched so that seam 55 is flat on the inside of liner 20.

[0027] Unfitted liner 60 has a forwardly facing opening 63. Wings 64, 66 extend forwardly along the sides of opening 63 which are respectively on the distal and medial sides of the leg of a wearer. Wings 64 and 66 are preferably asymmetrical as can be seen in Figures 5 and 6. Wing 64 which will eventually form inner flap 34 is slightly narrower than and does not extend as far down from cuff 38 as wing 66 which will eventually form outer flap 36. The forward edges of the upper portions of wings 64 and 66 project farther forward than the forward edges of the lower portions of wings 64 and 66.

[0028] Unfitted liner 60 is fitted to a wearer's foot and to the inside of boot shell 25 by the steps shown in Figures 7D through 7J. First, a convection oven is pre-heated to 115 C (240 °F). Pre-heating prevents liner 60 from being overheated by radiant energy from any exposed heating elements in the oven. Then, as shown in Figure 7D, unfitted liner 60 is placed in the oven and heated for approximately 10 minutes.

[0029] Unfitted liner 60 should not be heated to an excessive temperature. If material 42 is a closed cell foam material overheating can cause gas to escape from the cells of the foam. This can cause material 42 to lose some of its cushioning ability and can cause material 42 to shrink. Overheating unfitted liner 60 could also burn the foot of a wearer during the fitting process.

[0030] Before the heating of unfitted liner 60 is completed, padding (not shown) is placed around the wearer's toes. The padding prevents the resulting liner 20 from being so well fitted around the wearer's toes that the wearer's toes are held uncomfortably immobile. The padding can be cotton batting placed between the wearer's big toe and second toe, between the wearer's fourth and fifth toes, and sheet cotton batting placed over the ends of all of the toes and covering the last joints of the big and fifth toes. If the wearer has sensitive areas on his or her foot, additional padding may be applied to the sensitive areas to provide some space between those areas and liner 20. After the padding has been applied then the wearer's padded toes and foot are placed inside a short nylon stocking 70.

[0031] Next, as shown in Figure 7E, unfitted liner 60 is removed from the oven and the wearer's foot is placed into heated unfitted liner 60. After the wearer's foot is inside liner 60 wing 64 is wrapped across the front of the wearer's shin and ankle (Figure 7F) to form flap 34. As wing 64 is wrapped across the wearer's shin, the lowermost portion of wing 64 bends and forms a compound curve which conforms generally with the saddle-shaped curve of the wearer's foot and ankle. Wing 66 is then wrapped outside flap 34, in the opposite direction to wing 64, across the wearer's shin and ankle to form flap 36 (Figure 7G). As wing 66 is wrapped across the wearer's shin and ankle, the lowermost portion of wing 66 bends and conforms generally with the curve of the wearer's foot and ankle. The top edges of flaps 34 and 36 are then lined up and a second short nylon stocking 72 is rolled on over liner 60 (Figure 7H).

[0032] It is preferable that the wearer's foot be inserted into unfitted liner 60 before unfitted liner 60 is inserted into boot shell 25. If the wearer's foot were pushed into unfitted liner 60 after unfitted liner 60 was inserted into boot shell 25 then material 42 would tend to be forced ahead of the wearer's foot into the toe of shell 25 which could interfere with achieving an optimum fit.

[0033] At this point liner 60 is ready for final fitting. As shown in Figure 7I, boot shell 25 is held open and the wearer places his or her foot inside boot shell 25 until the wearer is standing in boot shell 25. During this step, material 42 is still above its thermoforming temperature. Because liner 60 is being pushed into boot shell 25 by the wearer's foot, material 42 tends to be squeezed slightly toward the wearer's heel as liner 60 presses against the walls of boot shell 25. This tends to increase the volume of material 42 in the region of the wearer's heel. As the wearer pushes his or her heel into position inside shell 25 material 42 flows into heel portion 31 around the wearer's heel and Achilles tendon to form a fitted heel pocket. To assist in the formation of the heel pocket the wearer's heel should be slightly raised and lowered after the wearer is standing inside boot shell 25. This avoids the formation of wrinkles in heel portion 31 and helps to shape the heel pocket.

[0034] The interior surface of boot shell 25 typically has small indentations and projections where, for example, buckles are riveted to boot shell 25 or a hinge mechanism is provided to allow flexion of shell 25 at a wearer's ankle. During the fitting process, material 42 flows around such projections and into such indentations to form a cast of the interior of boot shell 25. The close fit between liner 20 and boot shell 25 helps to hold liner 20 in place inside boot shell 25 when liner 20 is being worn inside boot shell 25. If it is desired to retain liner 20 even more firmly in place inside boot shell 25 then additional projections or indentations may be deliberately made on the inside surface of boot shell 25. During fitting liner 20 conforms to such indentations and/or projections.

[0035] After the wearer's foot and liner 60 have been inserted into boot shell 25, boot shell 25 is buckled closed around liner 60 as shown in Figure 7J. During the steps shown in Figures 7I and 7J the material 42 of unfitted liner 60 is compressed between the wearer's ankle and shell 25 and between the wearer's forefoot and shell 25 to form unfitted liner 60 to the wearer's ankle and forefoot in region 80 (Figure 1). At the same time, material 42 in outer flap 36 is indented around edge 54. It is necessary to accomplish all of these steps relatively quickly before unfitted liner 60 cools to a temperature below the thermoforming temperature of material 42.

[0036] The transformation of unfitted liner 60 into liner 20 is completed by allowing unfitted liner 60 to cool inside shell 25 until it has cooled to a temperature below the thermoforming temperature of material 42. The duration of this step is typically approximately 5 minutes. During the cooling step it is preferable for the wearer to move his or her foot so that the liner will provide a good fit to the wearer's foot and to boot shell 25. For example, the wearer may bang the heel of boot shell 25 on the ground to firmly seat the wearer's heel, wiggle the wearer's toes for approximately 1 minute and then stand for approximately 3 minutes applying forward pressure in the shin area to flex the boot forward at the ankle so that the wearer is standing in his or her customary skiing stance.

[0037] These fitting steps cause the outside surface of unfitted liner 60 to conform to the shape of the inside of boot shell 25 and the inside surface of liner 60 to conform to the shape of the wearer's foot (as modified by any padding which has been applied to the wearers foot). When material 42 cools to below its thermoforming temperature it retains the shape given to it when it was heated. Approximately 5 minutes after the step of placing the wearer's foot and unfitted liner 60 into boot-shell 25 the wearer's foot and liner 20 may be removed from boot shell 25, stockings 70, 72 and any padding may be removed from the wearer's foot and liner 20 may be reinserted into shell 25 where the wearer can check the fit. The process is then repeated for the wearer's other foot.

[0038] An advantage of practising this method with a liner 20 as described above is that in liner 20 flaps 34 and 36 overlap in region 80 between point 39 and the wearer's shin. Therefore, before fitting, there are two thicknesses of material 42 adjacent the top of the wearer's forefoot in region 80. The two layers of material 42 in region 80 provide enough material 42 in region 80 to ensure, if shell 25 is the correct size for the wearer, that there will be enough material 42 in region 80 and adjacent areas to completely fill the gap between the wearer's foot and shell 25. This facilitates a good fit to the wearer's forefoot which is can be important for fine control over the boot.

[0039] Liner 20 may also be formed by heating it as described above and placing it on a prosthesis (not shown) in the shape of a human foot and lower leg. Liner 20 may then be pressed against the prosthesis until it has cooled to below its thermoforming temperature. This method produces a liner which is not custom fitted to a wearer's foot and is therefore not preferred.

[0040] There are several advantages to manufacturing a ski boot with a liner 20 as described above. Firstly, the design of the liner keeps the top portion of the liner in snug contact with the wearer's shin and calf even when the wearer flexes his or her leg forward. As noted above, prior art boot liners which have a conventional front opening covered by a tongue tend to loosen about the wearer's calf as the wearer flexes his or her leg forward. This is because the wearer's shin applies a significant amount of pressure to the tongue when the wearer's leg is flexed forward. There is nothing to prevent the tongue from slipping forward relative to the rest of the liner. This can cause a space to form behind the wearer's calf. When the liner is not in snug contact with the wearer's calf it is easier for the wearer's heel to lift. The close fit of liner 20 in region 80 also helps to hold the wearer's foot and heel in place. Heel lift can take away from the wearer's comfort and control over the boot.

[0041] In a conventional boot the tendency for the cuff of the liner to loosen when the wearer flexes his or her leg forward at the ankle can be compensated for by making the shell of the boot tight when the wearer's leg is not flexed. When this is done there is no room for the liner to loosen when the wearer's leg is flexed forward. The disadvantage of making the boot shell tight is that a tight boot can be uncomfortable and may impair the circulation of blood to the wearer's foot.

[0042] The geometry of the cuff 38 of liner 20 is illustrated in Figure 8. Cuff 38 forms a generally rounded opening 86 to fit around the wearer's shin and calf. From a point 88 in the centre of opening 86, the angle subtended by the free end 54 of flap 34 and the free end 56 of flap 36 as seen from point 88 is preferably more than 100 degrees and is preferably approximately 130 degrees. This angle is illustrated as θ₁+θ₂ in Figure 8. The angle between the free end 54 of flap 34 and a mid-plane 90 which generally bisects liner 20 is preferably approximately the same as the angle between the free end 56 of flap 36 and mid-plane 90. That is, preferably θ₁ ≈ θ₂. When this is the case, and the wearer flexes his or her leg forward the pressure applied by the front of the wearer's shin to the inner surface of flap 34 as indicated by arrow 92 is almost entirely transmitted from flap 34 through flap 36 to boot shell 25. When the wearer flexes his or her leg forward the portion of liner 20 surrounding opening 86 remains snug but not tight. Preferably the free edge 54 of inner flap 34 does not extend far enough around a wearer's leg to press into the wearer's calf muscle.

[0043] When a person wearing a boot with a liner according to the invention flexes his or her leg forward the front of the wearer's shin presses on the inside of flap 34 as indicated by arrow 80 (Figure 8). Flap 36 is then compressed between flap 34 and shell 25. Cuff 38 of liner 20 cannot loosen about the wearer's calf and shin unless flap 34 slips relative to flap 36 (as indicated by arrows 82 and 83). However, the more the wearer flexes his or her leg forward in the boot, the more pressure is applied to squeeze flap 36 between flap 34 and shell 25 and the greater is the friction between flap 34 and flap 36. The friction between flaps 34 and 36 acts to prevent flap 36 from slipping relative to flap 34 and therefore prevents cuff 38 from loosening whenever the wearer's shin is exerting pressure on the inside of flap 20. Because cuff 38 of liner 20 is prevented from opening as described above, it is not necessary for the boot shell to be tight when the wearer's leg is not flexed. Thus a boot with a liner according to the invention may be more comfortable to wear than a boot with a conventional liner while providing the wearer with good control over the boot.

[0044] The friction between flap 34 and flap 36 may be made greater, and the resistance of liner 20 to opening may be consequentially increased, by providing one or more areas having an increased coefficient of friction on the outer surface of inner flap 34 or the inner surface of outer flap 36 or on both. This may be accomplished by roughening the surface of the material of which the flaps are made or by attaching one or more pieces of material having a relatively high coefficient of friction between flaps 34 and 36.

[0045] An advantage of the above-noted design is comfort. Overlapping flaps 20 and 22 provide two layers of padding in front of the wearer's shin. This prevents pressure spots on the wearer's shin and contributes to ideal boot flex characteristics. In a conventional boot liner with a tongue there is often a lump in the liner at the point at which the tongue attaches to the rest of the liner. This can cause a pressure spot on the top of the wearer's foot. This disadvantage is not present in a liner made according to the invention.

[0046] Figures 9 and 10 illustrate an alternative liner which is adapted for use in a hiking boot. Liner 120 shares the characteristics that it can be readily formed from a single piece of thermoformable material cut from a sheet and it is fitted to both the wearer's foot and the inside of a boot shell.

[0047] Liner 120 is made by cutting a blank 125 of thermoformable material 42 from a sheet of generally uniform thickness. Material 42 is preferably laminated on both sides with fabric 44 as described above. Blank 125 is formed into an unfitted liner by joining edge 127 to edge 129 between point 131 and points 132, and 133 to form seam 135. Point 137 on liner 120 corresponds to points 132 and 133. The unfitted liner is formed into liner 120 by the same sequence of steps described above with respect to liner 20 except that the steps related to forming flaps 34 and 36 are omitted because liner 120 has no flaps. The inner surface of liner 120 is fitted to a wearer's foot and the outer surface of liner 120 is fitted to the inside of a boot shell (not shown).

[0048] As will be apparent to those skilled in the art in the light of the foregoing disclosure, many alterations and modifications are possible in the practice of this invention without departing from the scope of claims 1-16.

Claims

1. A method for forming a custom-fitted sport boot liner for wearing inside a sport boot shell, said liner having a rounded opening (86) for receiving a wearer's lower-leg and comprising a thermoformable material (42), said material (42) having a thermoforming temperature, said method comprising the steps of:

(a) providing an unfitted liner (60) having a hollow foot receiving portion and a hollow lower-leg receiving portion, said hollow lower-leg receiving portion having first and second side edges (54), (56); and

(b) fitting said unfitted liner (60) to said wearer's foot by steps including heating said thermoformable material to a temperature above said thermoforming temperature; placing a wearer's foot and lower leg into said unfitted liner (60) with said foot in said foot-receiving portion and said lower leg in said lower-leg receiving portion; and, allowing said unfitted liner (60) to cool to a temperature below said thermoforming temperature;

said method characterized by:

(c) selecting an unfitted liner (60) comprising a sheet (40) of a thermoformable material (42) having first and second side edges (54), (56), said side edges defining free edges of first and second thermoformable wings (64), (66), each of said wings (64), (66) capable of being wrapped substantially completely across a wearer's shin;

(d) heating said unfitted liner (60) to a temperature above said thermoforming temperature before said step of placing a wearer's foot and lower leg into said unfitted liner (60); and

(e) fitting said liner to said wearer's foot by the steps of:

(f) wrapping said first wing (64) in front of said wearer's lower leg in a first direction until said first wing extends substantially entirely across said wearer's lower leg;

(g) wrapping said second wing (66) in front of said wearer's lower leg outside of and overlapping with said first wing (64) in a second direction, opposite to said first direction, until said second wing extends substantially entirely across said wearer's lower leg to form a double thickness of said thermoformable material in an overlap region forwardly adjacent said wearer's shin, said overlap region subtending an angle of at least 100 degrees relative to a point (88) centred in said rounded opening (86); and

(h) placing said wearer's foot and lower leg and unfitted liner (60) inside said sport boot shell (25) to simultaneously shape an inside surface of said unfitted liner (60) to conform to said wearer's foot and lower leg and an outside surface of said unfitted liner (60) to conform to an inside surface of said sport boot shell (25).

2. The method of claim 1 further characterized in that said first and second wings form a double thickness of thermoplastic material in a region (80) upwardly adjacent said wearer's forefoot and said step of wrapping said first wing (64) in front of said wearer's lower leg is further characterized by bending a lower portion of said first wing (64) to form a compound curve conforming generally to a compound curve defined by forward facing portions of said wearer's forefoot, ankle and shin.

3. The method of claim 2 further characterized in that said step of wrapping said second wing (66) in front of said wearer's lower leg further comprises bending a lower portion of said second wing (66) to conform generally to said compound curve defined said first wing (64) in said region (80).

4. The method of claim 3 further characterized in that said step of fitting said liner to said wearer's foot is further characterized by placing an elastic sleeve (72) around said unfitted liner (60) to compress said unfitted liner (60) against said wearer's foot and lower leg before said step of placing said wearer's foot and lower leg and unfitted liner (60) inside said sport boot shell (25).

5. The method of Claim 4 further characterized in that said first direction is a direction from the outside of said wearer's foot toward the inside of said wearer's foot.

6. The method of Claim 4 further characterized in that said unfitted liner (60) is formed from a single unitary flat blank (40) of thermoplastic foam material (42) having a uniform thickness.

7. The method of Claim 6 further characterized in that said inner surface of said sport boot shell (25) comprises a plurality of indentations and said step of shaping an outside surface of said unfitted liner (60) to conform to an inside surface of said sport boot shell (25) comprises forming projecting areas on said outer surface of said liner (20) corresponding to said indentations.

8. A sport boot liner (20) for wearing inside a sport boot shell (25), said liner (20) comprising a hollow generally-horizontal foot receiving portion having a central longitudinal axis and a hollow lower-leg receiving portion extending generally vertically from a rearward end of said foot-receiving portion; said foot receiving portion having a heel-receiving portion (28) at said rearward end, a toe-receiving portion at a forward end and a forefoot region (80) on an upper surface of said foot-receiving portion forward from said lower-leg receiving portion and rearward from said toe-receiving portion; said lower-leg receiving portion comprising a rearward facing calf receiving portion (29), an ankle-receiving area, a forward-facing shin receiving portion (27) extending laterally entirely across a forward-facing face of said lower-leg receiving portion and extending vertically from said foot receiving portion to a cuff (38), said cuff (38) being above a horizontal plane through said ankle-receiving area and defining a rounded opening (86), and first and second side edges (54, 56) defining a further opening (63) for insertion of a wearer's lower-leg; characterized by:

(a) said first and second side edges (54, 56) defining free edges of first and second thermoformable wings on a sheet of thermoformable material;

(b) said side edge (54) defining a free edge of a first curved flap (34) wrapped in a first direction (34, 36) substantially entirely across said shin receiving portion;

(c) said side edge (56) defining a free edge of a second curved flap (36) wrapped in a second direction, opposite to said first direction, and overlapping with said first flap in an overlap region which subtends an angle of at least 100 degrees relative to a point (88) centred in said rounded opening (86) and which extends at least over a region (80) between said horizontal plane and a point (39) located centrally on said upper surface of said foot-receiving portion forward from said ankle-receiving portion and rearward from said toe-receiving portion; and,

(d) said first and second curved flaps comprising curved sheets of thermoformable foam material.

9. The sport boot liner of Claim 8 further characterized in that said overlap region extends vertically between said top edge (38) and said foot receiving portion.

10. The sport boot liner of Claim 8 further characterized in that said sheets of thermoformable foam material comprise a thermoplastic foam material (42) having a thermoforming temperature not greater than 115 C.

11. The sport boot liner of claim 10 further characterized in that said overlap region extends vertically between said top edge (38) and said point (39), said overlap region having a saddle-shaped area of compound curvature in said forefoot region (80), said saddle shaped area having an inner surface shaped to conform to contours of a human foot.

12. The sport boot liner of claim 8 further characterized in that, in said region adjacent said top edge, relative to said point (88), said overlap region subtends angles greater than 40 degrees to each of two sides of a vertical line bisecting said shin receiving portion.

13. The sport boot liner of claim 12 characterized in that said angles are greater than 50 degrees.

14. The sport boot liner of claim 10 further characterized in that said lower leg receiving portion and said foot receiving portion comprise a unitary sheet of thermoformable foam material.

15. The sport boot liner of claim 14 further characterized by a layer of stretch fabric (44) laminated to and covering each side of said unitary sheet of thermoformable foam material (42).

16. The sport boot liner of Claim 8, 9 or 10 further characterized by a layer of friction material between said first and second flaps (34,36).

Ansprüche

1. Verfahren zum Formen eines nach Maß angepaßten Sportstiefel-Innenschuhs, der im Inneren einer Sportstiefelschale zu tragen ist, wobei der Innenschuh eine gerundete Öffnung (86) zur Aufnahme des Unterschenkels eines Trägers hat und ein warmformbares Material (42) aufweist, wobei dieses Material (42) eine Warmformtemperatur hat, wobei das Verfahren die folgenden Schritte aufweist:

(a) Bereitstellen eines nichtangepaßten Innenschuhs (60), der einen hohlen Fußaufnahmebereich und einen hohlen Unterschenkelaufnahmebereich hat, wobei der hohle Unterschenkelaufnahmebereich einen ersten und einen zweiten Seitenrand (54),(56) hat; und

(b) Anpassen des nichtangepaßten Innenschuhs (60) an den Fuß des Trägers durch die Schritte: Erwärmen des warmformbaren Materials auf eine Temperatur oberhalb der Warmformtemperatur; Plazieren eines Fußes und Unterschenkels des Trägers in dem nichtangepaßten Innenschuh (60), wobei der Fuß in dem Fußaufnahmebereich und der Unterschenkel in dem Unterschenkelaufnahmebereich plaziert wird; und Abkühlenlassen des nichtangepaßten Innenschuhs (60) auf eine Temperatur unterhalb der Warmformtemperatur;

wobei das Verfahren gekennzeichnet ist durch die folgenden Schritte:

(c) Wählen eines nichtangepaßten Innenschuhs (60), der einen Flächenkörper (40) aus einem warmformbaren Material (42) aufweist und einen ersten und einen zweiten Seitenrand (54),(56) hat, wobei diese Seitenränder freie Ränder eines ersten und eines zweiten warmformbaren Flügels (64),(66) definieren und jeder Flügel (64),(66) imstande ist, im wesentlichen vollständig über ein Schienbein des Trägers gewickelt zu werden;

(d) Erwärmen des nichtangepaßten Innenschuhs (60) auf eine Temperatur oberhalb der Warmformtemperatur vor dem Schritt des Plazierens eines Fußes und Unterschenkels des Trägeres in dem nichtangepaßten Innenschuh (60); und

(e) Anpassen des Innenschuhs an den Fuß des Trägers durch die folgenden Schritte:

(f) Wickeln des ersten Flügels (64) vor dem Unterschenkel des Trägers in einer ersten Richtung, bis sich der erste Flügel im wesentlichen vollständig um den Unterschenkel des Trägers erstreckt;

(g) Wickeln des zweiten Flügels (66) vor dem Unterschenkel des Trägers an der Außenseite des ersten Flügels (64) und in Überlappung damit in einer zweiten Richtung entgegengesetzt zu der ersten Richtung, bis sich der zweite Flügel im wesentlichen vollständig über den Unterschenkel des Trägers erstreckt, um eine doppelte Dicke des warmformbaren Materials in einem Überlappungsbereich vorn angrenzend an das Schienbein des Trägers zu bilden, wobei der Überlappungsbereich einem Winkel von wenigstens 100° relativ zu einem Punkt (88) gegenüberliegt, der in der gerundeten Öffnung (86) zentriert ist; und

(h) Plazieren des Fußes und Unterschenkels des Trägers und des nichtangepaßten Innenschuhs (60) in der Sportstiefelschale (25), um gleichzeitig eine innenseitige Oberfläche des nichtangepaßten Innenschuhs (60) so, daß sie an den Fuß und den Unterschenkel des Trägers angepaßt ist, und eine außenseitige Oberfläche des nichtangepaßten Innenschuhs (60) so, daß sie an eine innenseitige Oberfläche der Sportstiefelschale (25) angepaßt ist, zu formen.

2. Verfahren nach Anspruch 1, ferner dadurch gekennzeichnet, daß der erste und der zweite Flügel eine doppelte Dicke aus Thermoplastmaterial in einem dem vorderen Teil des Fußes des Trägers nach oben benachbarten Bereich (80) bilden und daß der Schritt des Wickelns des ersten Flügels (64) vor dem Unterschenkel des Trägers ferner gekennzeichnet ist durch Biegen eines unteren Bereichs des ersten Flügels (64), so daß er eine zusammengesetzte Krümmung bildet, die allgemein an eine zusammengesetzte Krümmung angepaßt ist, die durch nach vorn weisende Bereiche des vorderen Teils des Fußes, des Knöchels und des Schienbeins des Trägers definiert ist.

3. Verfahren nach Anspruch 2, ferner dadurch gekennzeichnet, daß der Schritt des Wickelns des zweiten Flügels (66) vor dem Unterschenkel des Trägers das Biegen eines unteren Bereichs des zweiten Flügels (66) aufweist, so daß er allgemein an die zusammengesetzte Krümmung angepaßt ist, die von dem ersten Flügel (64) in diesem Bereich (80) definiert ist.

4. Verfahren nach Anspruch 3, dadurch gekennzeichnet, daß der Schritt des Anpassens des Innenschuhs an den Fuß des Trägers ferner gekennzeichnet ist durch Anbringen einer elastischen Hülse (72) um den nichtangepaßten Innenschuh (60) herum, um den nichtangepaßten Innenschuh (60) an den Fuß und den Unterschenkel des Trägers anzupressen, und zwar vor dem Schritt des Plazierens des Fußes und des Unterschenkels des Trägers und des nichtangepaßten Innenschuhs (60) im Inneren der Sportstiefelschale (25).

5. Verfahren nach Anspruch 4, ferner dadurch gekennzeichnet, daß die erste Richtung eine Richtung von der Außenseite des Fußes des Trägers zu der Innenseite des Fußes des Trägers ist.

6. Verfahren nach Anspruch 4, ferner dadurch gekennzeichnet, daß der nichtangepaßte Innenschuh (60) aus einem einzigen einstückigen flachen Zuschnitt (40) aus Thermoplast-Schaumstoff (42), der gleichmäßige Dicke hat, geformt ist.

7. Verfahren nach Anspruch 6, ferner dadurch gekennzeichnet, daß die innere Oberfläche der Sportstiefelschale (25) eine Vielzahl von Vertiefungen aufweist und daß der Schritt des Formens einer außenseitigen Oberfläche des nichtangepaßten Innenschuhs (60) zur Anpassung an eine innenseitige Oberfläche der Sportstiefelschale (25) das Formen von den Vertiefungen entsprechenden vorspringenden Bereichen an der äußeren Oberfläche des Innenschuhs (20) aufweist.

8. Sportstiefel-Innenschuh (20) zum Tragen in einer Sportstiefelschale (25), wobei der Innenschuh (20) einen hohlen, allgemein horizontalen Fußaufnahmebereich, der eine zentrale Längsachse hat, und einen hohlen Unterschenkelaufnahmebereich aufweist, der sich allgemein vertikal von einem hinteren Ende des Fußaufnahmebereichs erstreckt; wobei der Fußaufnahmebereich einen Fersenaufnahmebereich (28) an dem hinteren Ende, einen Zehenaufnahmebereich an einem vorderen Ende und einen Vorderfußbereich (80) an einer oberen Oberfläche des Fußaufnahmebereichs vor dem Unterschenkelaufnahmebereich und hinter dem Zehnenaufnahmebereich hat; wobei der Unterschenkelaufnahmebereich aufweist: einen nach rückwärts weisenden Wadenaufnahmebereich (29), einen Knöchelaufnahmebereich, einen nach vorn weisenden Schienbeinaufnahmebereich (27), der sich quer vollständig über eine nach vorn weisende Fläche des Unterschenkelaufnahmebereichs und vertikal von dem Fußaufnahmebereich zu einer Manschette (38) erstreckt, wobei die Manschette (38) oberhalb einer Horizontalebene durch den Knöchelaufnahmebereich ist und eine gerundete Öffnung (86) definiert, und einen ersten und einen zweiten Seitenrand (54, 56), die eine weitere Öffnung (63) zum Einführen des Unterschenkels eines Trägers definieren; dadurch gekennzeichnet, daß:

(a) der erste und der zweite Seitenrand (54, 56) freie Ränder eines ersten und eines zweiten warmformbaren Flügels an einem Flächenkörper aus warmformbarem Material definieren;

(b) der Seitenrand (54) einen freien Rand einer ersten gekrümmten Lasche (34) definiert, die in einer ersten Richtung (34, 36) im wesentlichen vollständig über den Schienbeinaufnahmebereich gewickelt ist;

(c) der Seitenrand (56) einen freien Rand einer zweiten gekrümmten Lasche (36) definiert, die in einer zweiten Richtung entgegengesetzt zu der ersten Richtung gewickelt ist und die erste Lasche in einem Überlappungsbereich überlappt, der einem Winkel von wenigstens 100° relativ zu einem Punkt (88), der in der gerundeten Öffnung (86) zentriert ist, gegenüberliegt und sich wenigstens über eine Zone (80) zwischen der Horizontalebene und einem Punkt (39) erstreckt, der zentral auf der oberen Oberfläche des Fußaufnahmebereichs vorwärts von dem Knöchelaufnahmebereich und rückwärts von dem Zehenaufnahmebereich liegt; und

(d) die erste und die zweite gekrümmte Lasche gekrümmte Flächenkörper aus warmformbarem Schaumstoff aufweisen.

9. Sportstiefel-Innenschuh nach Anspruch 8, ferner dadurch gekennzeichnet, daß der Überlappungsbereich sich vertikal zwischen dem oberen Rand (38) und dem Fußaufnahmebereich erstreckt.

10. Sportstiefel-Innenschuh nach Anspruch 8, ferner dadurch gekennzeichnet, daß die Flächenkörper aus warmformbarem Schaumstoff einen thermoplastischen Schaumstoff (42) aufweisen, der eine Warmformtemperatur von nicht mehr als 115 °C hat.

11. Sportstiefel-Innenschuh nach Anspruch 10, ferner dadurch gekennzeichnet, daß sich der Überlappungsbereich vertikal zwischen dem oberen Rand (38) und dem Punkt (39) erstreckt, wobei der Überlappungsbereich eine sattelförmige Zone einer zusammengesetzten Krümmung in dem Vorderfußbereich (80) hat und die sattelförmige Zone eine innere Oberfläche hat, die so geformt ist, daß sie an Konturen eines menschlichen Fußes angepaßt ist.

12. Sportstiefel-Innenschuh nach Anspruch 8, ferner dadurch gekennzeichnet, daß in dem Bereich benachbart dem oberen Rand relativ zu dem Punkt (88) der Überlappungsbereich Winkeln von mehr als 40° zu jeder von zwei Seiten einer Vertikallinie gegenübersteht, die den Schienbeinaufnahmebereich halbiert.

13. Sportstiefel-Innenschuh nach Anspruch 12, dadurch gekennzeichnet, daß die Winkel größer als 50° sind.

14. Sportstiefel-Innenschuh nach Anspruch 10, ferner dadurch gekennzeichnet, daß der Unterschenkelaufnahmebereich und der Fußaufnahmebereich einen einstückigen Flächenkörper aus warmformbarem Schaumstoff aufweisen.

15. Sportstiefel-Innenschuh nach Anspruch 14, ferner gekennzeichnet durch eine Schicht aus Stretchgewebe (44), das auf jede Seite des einstückigen Flächenkörpers aus warmformbarem Schaumstoff (42) kaschiert ist und sie überdeckt.

16. Sportstiefel-Innenschuh nach Anspruch 8, 9 oder 10, ferner gekennzeichnet durch eine Schicht aus Reibungsmaterial zwischen der ersten und der zweiten Lasche (34, 36).

Revendications

1. Procédé de formage d'un chausson anatomiquement conformable pour chaussure de sport, destiné à être porté à l'intérieur de la coque d'une chaussure de sport, ledit chausson comportant une ouverture circulaire (86) pour l'introduction de la partie inférieure de la jambe de l'utilisateur et étant réalisé dans une matière thermoformable (42), ladite matière (42) ayant une température de thermoformage, ledit procédé comprenant les étapes consistant à :

(a) réaliser un chausson non conformé anatomiquement (60), comportant une partie creuse formant logement pour le pied et une partie creuse formant logement pour la partie inférieure de la jambe, ladite partie creuse formant logement pour la partie inférieure de la jambe présentant des premier et second bords latéraux (54), (56) ; et

(b) adapter ledit chausson non conformé anatomiquement (60) à la morphologie du pied dudit utilisateur au moyen des étapes consistant à chauffer ladite matière thermoformable à une température supérieure à ladite température de thermoformage ; à introduire le pied et la partie inférieure de la jambe de l'utilisateur dans ledit chausson non conformé anatomiquement (60), ledit pied étant placé dans ladite partie formant logement pour le pied et ladite partie inférieure de la jambe dans ladite partie formant logement pour la partie inférieure de la jambe ; et en laissant ledit chausson non conformé anatomiquement (60) se refroidir à une température inférieure à ladite température de thermoformage ;

   ledit procédé caractérisé en ce que :

(c) l'on choisit un chausson non conformé anatomiquement (60) se composant d'une feuille (40) de matière thermoformable (42) ayant des premier et second bords latéraux (54), (56), lesdits bords latéraux définissant les bords libres de premier et second flancs thermoformables (64), (66), chacun desdits flancs (64), (66) pouvant être rabattu sensiblement de façon complète sur le devant de la jambe de l'utilisateur ;

(d) on chauffe ledit chausson non conformé anatomiquement (60) à une température supérieure à ladite température de thermoformage avant ladite étape consistant à placer le pied et la partie inférieure de la jambe de l'utilisateur dans ledit chausson non conformé anatomiquement (60) ; et

(e) on conforme ledit chausson à la morphologie du pied dudit utilisateur au moyen des étapes consistant à :

(f) rabattre ledit premier flanc (64) sur l'avant de la partie inférieure de la jambe dudit utilisateur dans une première direction jusqu'à ce que ledit premier flanc recouvre sensiblement complètement la partie inférieure de la jambe dudit utilisateur ;

(g) rabattre ledit second flanc (66) sur l'avant de ladite partie inférieure de la jambe dudit utilisateur à l'extérieur de et en recouvrement sur ledit premier flanc (64) dans une seconde direction, opposée à ladite première direction, jusqu'à ce que ledit second flanc recouvre sensiblement complètement la partie inférieure de la jambe dudit utilisateur de manière à constituer une double épaisseur de ladite matière thermoformable dans une région en chevauchement vers l'avant adjacente audit devant de la jambe de l'utilisateur, ladite région en chevauchement sous-tendant un angle d'au moins 100 degrés par rapport à un point (88) correspondant au centre de ladite ouverture circulaire (86) ; et

(h) introduire ledit pied et ladite partie inférieure de la jambe dudit utilisateur et ledit chausson non conformé anatomiquement (60) à l'intérieur de ladite coque de chaussure de sport (25) pour simultanément profiler la surface intérieure dudit chausson non conformé anatomiquement (60) pour qu'elle épouse les contours du pied et de la partie inférieure de la jambe dudit utilisateur et la surface extérieure dudit chausson non conformé anatomiquement (60) pour qu'elle épouse les contours de la surface intérieure de ladite coque de chaussure de sport (25).

2. Procédé selon la revendication 1, caractérisé en outre en ce que lesdits premier et second flancs constituent une double épaisseur de matière thermoplastique dans une zone (80) vers le haut adjacente au devant du pied dudit utilisateur et en ce que ladite étape consistant à rabattre ledit premier flanc (64) sur l'avant de la partie inférieure de la jambe dudit utilisateur est en outre caractérisée en ce que l'on cintre la partie inférieure dudit premier flanc (64) pour former une courbe composée correspondant d'une manière générale à la courbe composée définie par les parties orientées vers l'avant du devant du pied, de la cheville et du devant de la jambe dudit utilisateur.

3. Procédé selon la revendication 2, caractérisé en outre en ce que ladite étape consistant à rabattre ledit second flanc (66) sur l'avant de ladite partie inférieure de la jambe dudit utilisateur comprend en outre celle consistant à cintrer la partie inférieure dudit second flanc (66) pour correspondre d'une manière générale à ladite courbe composée définie par ledit premier flanc (64) dans ladite zone (80).

4. Procédé selon la revendication 3, caractérisé en outre en ce que ladite étape consistant à adapter ledit chausson à la morphologie du pied dudit utilisateur est en outre caractérisée par le fait que l'on place un manchon élastique (72) autour dudit chausson non conformé anatomiquement (60) pour comprimer ledit chausson non conformé anatomiquement (60) contre le pied et la partie inférieure de la jambe dudit utilisateur avant ladite étape consistant à introduire le pied et la partie inférieure de la jambe dudit utilisateur et le chausson non conformé anatomiquement (60) à l'intérieur de ladite coque de chaussure de sport (25).

5. Procédé selon la revendication 4, caractérisé en outre en ce que ladite première direction est une direction qui va de l'extérieur du pied dudit utilisateur vers l'intérieur du pied dudit utilisateur.

6. Procédé selon la revendication 4, caractérisé en outre en ce que ledit chausson non conformé anatomiquement (60) est réalisé par formage à partir d'une ébauche plate d'une seule pièce (40) de mousse thermoplastique (42) ayant une épaisseur uniforme.

7. Procédé selon la revendication 6, caractérisé en outre en ce que ladite surface intérieure de ladite coque de chaussure de sport (25) comprend une pluralité d'empreintes et en ce que ladite étape consistant à profiler la surface extérieure dudit chausson non conformé anatomiquement (60) pour qu'elle épouse la surface intérieure de ladite coque de chaussure de sport (25) comprend la réalisation par formage de zones formant saillies sur ladite surface extérieure dudit chausson (20) en correspondance avec lesdites empreintes.

8. Chausson pour chaussure de sport (20) destiné à être porté à l'intérieur d'une coque de chaussure de sport (25), ledit chausson (20) comprenant une partie creuse généralement horizontale formant logement pour le pied, ayant un axe longitudinal central, et une partie creuse formant logement pour la partie inférieure de la jambe, se prolongeant d'une manière générale verticalement depuis l'extrémité arrière de ladite partie formant logement pour le pied ; ladite partie formant logement pour le pied comportant une partie formant logement pour le talon (28) au niveau de ladite extrémité arrière, une partie formant logement pour les orteils au niveau de l'extrémité avant et une partie d'avant du pied (80) sur la surface supérieure de ladite partie formant logement pour le pied sur l'avant de ladite partie formant logement pour la partie inférieure de la jambe et sur l'arrière de ladite partie formant logement sur les orteils ; ladite partie formant logement pour la partie inférieure de la jambe comprenant une partie formant logement pour le mollet (29) orientée vers l'arrière, une partie formant logement pour la cheville, une partie formant logement pour le devant de la jambe (27) orientée vers l'avant, s'étendant latéralement sur la totalité de la face orientée vers l'avant de ladite partie formant logement pour la partie inférieure de la jambe et se prolongeant verticalement de ladite partie formant logement pour le pied jusqu'à une collerette (38), ladite collerette (38) se trouvant au-dessus d'un plan horizontal passant par ladite zone formant logement pour la cheville et définissant une ouverture circulaire (86) et des premier et second bords latéraux (54, 56) définissant une autre ouverture (63) pour l'introduction de la partie inférieure de la jambe de l'utilisateur, caractérisé en ce que :

(a) lesdits premier et second bords latéraux (54, 56) définissent les bords libres de premier et second flancs thermoformables sur une feuille de matière thermoformable ;

(b) ledit bord latéral (54) définit le bord libre d'un premier rabat incurvé (34) rabattu dans une première direction (34, 36) recouvrant sensiblement dans son intégralité ladite partie formant logement pour le devant de la jambe ;

(c) ledit bord latéral (56) définit le bord libre d'un second rabat incurvé (36) rabattu dans une seconde direction, opposée à la première direction, et se chevauchant avec ledit premier rabat dans une région en chevauchement qui sous-tend un angle d'au moins 100 degrés par rapport à un point (88) correspondant au centre de ladite ouverture arrondie (86) et qui s'étend au moins sur une zone (80) entre ledit plan horizontal et un point (39) placé au centre sur ladite surface supérieure de ladite partie formant logement pour le pied, vers l'avant depuis ladite partie formant logement pour la cheville et vers l'arrière depuis ladite partie formant logement pour les orteils ; et

(d) lesdits premier et second rabats incurvés sont constitués par des feuilles de mousse thermoformable incurvées.

9. Chausson pour chaussure de sport selon la revendication 8, caractérisé en outre en ce que ladite région en chevauchement s'étend dans le plan vertical entre ledit bord supérieur (38) et ladite partie formant logement pour le pied.

10. Chausson pour chaussure de sport selon la revendication 8, caractérisé en outre en ce que lesdites feuilles de mousse thermoformable sont réalisées dans une mousse thermoplastique (42) ayant une température de thermoformage ne dépassant pas 115°C.

11. Chausson pour chaussure de sport selon la revendication 10, caractérisé en outre en ce que ladite région en chevauchement s'étend dans le plan vertical entre ledit bord supérieur (38) et ledit point (39), ladite région en chevauchement présentant une zone en forme d'étrier à courbure composée dans ladite région de l'avant du pied (80), ladite zone en forme d'étrier ayant une surface intérieure profilée de manière à épouser la morphologie d'un pied humain.

12. Chausson pour chaussure de sport selon la revendication 8, caractérisé en outre en ce que, dans ladite région adjacente audit bord supérieur, par rapport audit point (88), ladite région en chevauchement sous-tend des angles supérieurs à 40 degrés par rapport à chacun des deux côtés d'une ligne verticale coupant en deux parties égales ladite partie formant logement pour le devant de la jambe.

13. Chausson pour chaussure de sport selon la revendication 12, caractérisé en ce que lesdits angles sont supérieurs à 50 degrés.

14. Chausson pour chaussure de sport selon la revendication 10, caractérisé en outre en ce que ladite partie formant logement pour la partie inférieure de la jambe et ladite partie formant logement pour le pied sont faites d'une feuille d'une seule pièce de mousse thermoformable.

15. Chausson pour chaussure de sport selon la revendication 14, caractérisé en outre par la présence d'une couche de tissu élastique (44) superposée sur et recouvrant chaque face de ladite feuille d'une seule pièce de mousse thermoformable (42).

16. Chausson pour chaussure de sport selon la revendication 8, 9 ,ou 10, caractérisé en outre par la présence d'une couche de matière de friction entre lesdits premier et second rabats (34, 36).

Drawing